Recently, Microsoft released Internet Explorer 8, which boasted much better standards compliance than previous iterations of the browser. While it passed the Acid2 test, IE8 failed miserably in the Acid3 test, and many people criticised Microsoft for it. Microsoft Australia's Nick Hodge has stated that Microsoft purposefully decided not to support Acid3, because the test tests against draft standards.

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I think this is a very positive sign that MS is finally treating it's position as market leader responsibly. They are conforming preciesly to the published standards of the W3C and no more. This leaves the W3C free to make ammendments to their draft standards that won't conflict with the most widely deployed implementation.

This is the exact opposite of the old, infamous "embrace, extend, extinguish" policy of the early days of the web.

I would applaud that attitude if they really followed it. The biggest gripe since the standardisation it was even worse than ignoring png until ie7 was the non implementation of SVG in IE.
As I said Microsoft was able to fork an incompatible clone of it for Silverlight, but yet they are not able to implement the proper W3C standard for the IE! The same goes for a load of other finalized standards tested in ACID3. The funny thing is that history seems to repeat itself with EcmaScript4. Everybody wants to integrate it into the browsers. Microsoft does not!